Internet Protocol Television (IPTV) supports multi-media content (e.g., television) delivered via the various technologies used for computer networks. Single program transport streams (SPTS) or multiple program transport streams (MPTS) may be sourced by the same network operator that owns or controls the final mile to the consumer's premises. This control over delivery enables the service provider to guarantee a specific quality of service (QoS) level and offer an enhanced user experience, such as a better on-screen program guide, various interactive services and so on.
For residential users, IPTV is often provided in conjunction with Video on Demand (VOD) services and may be bundled with Internet services such as Web access and voice over IP (VoIP) telephony services. IPTV is typically supplied by a service provider using a closed network infrastructure. For business users, IPTV may be used to deliver multi-media content (e.g., video conferencing) over corporate LANs.
A known issue with IPTV is the loss of packets in a subscriber's loop, which can cause visual and/or audible artifacts in the reproduced video and/or audio at the subscriber's presentation device. When data is missing in the stream, a decoder may respond by skipping the relevant frames which results in a transient freeze of the video or a mute in the audio. Alternatively, the decoder may estimate the missing data using default values, interpolation and similar error concealment methods. Since such estimation is often inaccurate, implementing these methods frequently result in visible or audible impairments.